﻿using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading.Tasks;

namespace ConsoleApp1
{
    class Program
    {
        static void Main(string[] args)
        {
            // 1.
            Random ran = new Random();
            int[] arr = new int[10];
            for (int i = 0; i < arr.Length;)
            {
                int num = new Random().Next(1, 11);
                if (!arr.Contains(num))
                {
                    arr[i] = num;
                    i++;
                }
            }

            // 2.
            double num2 = ran.NextDouble() * 5;
            Console.WriteLine(num2.ToString("f2"));

            // 3. 
            double num3 = (ran.NextDouble() * 3) + 4;
            Console.WriteLine(num3.ToString("f2"));

            // 4. 
            Regex regex = new Regex(@"^\w+(\.\w)?@\w+(\.\w)+$");
            string input = Console.ReadLine();
            Console.WriteLine(regex.IsMatch(input));

            // 5.
            regex = new Regex(@"^1[3-9]{1}\d{9}$");
            string input2 = Console.ReadLine();
            Console.WriteLine(regex.IsMatch(input2));
        }
    }




}
